Composite coatings with excellent technical properties are produced by inclusion of selected functional materials in an electrolytic or electroless deposited metal matrix.
The production of such composite coatings is disclosed in U.S. Pat. No. 5,076,897. The functional substances to be incorporated in the coating are introduced into an electrolyte containing the matrix material. In the subsequent electrolytic deposition of the matrix material onto the surface of a structural part or substrate, the included substances are incorporated into the matrix.
U.S. Pat. No. 5,076,897 requires the use of a complex and expensive apparatus for this purpose, since the bath containing the inclusion substances is kept continually in motion in order to avoid sedimentation effects, and the article to receive the coating is subjected to multiaxial motions in order to equalize the incorporation of the substances in the coating on the surface of the article.
Other disadvantages of the known process are that the particle size of the substance to be incorporated in the coating is limited to less than 20 .mu.m and the amount of incorporated substance cannot exceed 25 vol. %. Due to the risk of short circuit in the electrolyte, electrically conductive substances cannot be incorporated in the matrix. Single layers, which do not contain multiple superimpositions of the substance to be incorporated, cannot be prepared with this process. In structural parts of complex shape, fluctuations in the amount of incorporated substance occur which cannot be completely compensated by motion of the structural part and the bath. The care and maintenance of the bath is difficult and expensive.